A system is known in which a file storage disposed at each of a plurality of points such as branch offices of a company shares a directory and/or a file via a cloud storage. A user at each point recognizes a storage location of a file based on a directory path in a file system. Therefore, the plurality of file storages must maintain consistency of a directory path.
In order to maintain the consistency of a directory path, a file storage acquires information on a directory manipulation performed at another point and applies the manipulation to its own file system. Due to this process, a directory tree can be synchronized among the plurality of file storages.
PTL 1 describes a first client system changing contents a folder, whereby the change is applied to a synchronized folder of a host system and a second client system acquires a current version of contents of the synchronized folder.